A robot is chiefly divided into an industrial robot used in an industrial spot and a human like robot having a similar form to a human being. The industrial robot performs a task through remote control or performs a simple repetition task having the degree of freedom of 1˜2 or a task having the degree of freedom of 3 using electronic control in an environment in which a human being finds difficult to perform a task. The industrial robot is used as a worker for realizing a Flexible Manufacturing System (FMS).
The human like robot has a human like form and corresponds to the ultimate object of robot technology. The human like robot is chiefly divided into a humanoid robot and an android robot. The humanoid robot refers to a robot which has a similar outward appearance to a human being, has two arms, two legs, and the head, and can move to some extent. The humanoid robot includes ASIMO developed by Honda Motor Co., Ltd. in Japan, HUBO developed by KAIST in Korea, and so on.
The android robot refers to a robot looking like a human being, and it is rarely distinguished from a human being in an appearance. Although the android robot has not yet been fabricated, research into a robot capable of expressing feelings is in progress. Accordingly, various robots are being developed. Robots developed so far express metal states, feelings, etc. through mechanical faces after a human's face. The robots include Kissmet simulated from the muscle of a face mechanically and developed by MIT, SAYA fabricated by Tokyo University of Japan so that it is similar to a human' skin using silicon, and so on.
Only the facial part of the android robot is called an android face robot. As shown in FIG. 1, the android face robot is designed to be similar to a human being in order to implement various expressions of feelings. The android face robot includes the skin, a facial skeleton, and an appliance unit for moving the facial muscle. That is, unlike other robots having a casing made of steel, the android face robot maintains its shape by fixing an outside skin 110 made of soft material, such as silicon or hot foam, to an inside skin 120 corresponding to a facial skeleton by using an adhesive so that the android face robot has the skin similar to an actual human skin. Furthermore, an appliance unit 130 corresponding to the brain of a human being is organically connected to and placed within the inside skin 120 and is formed of a microprocessor, sensors, a motor, and an actuator so that it can implement a face muscle motion and expressions of feelings. The appliance unit 130 is connected to the inside skin by using a wires or a thread having less rigidity. When the appliance unit 130 moves, the inside skin 120 and the outside skin 110 are also designed to move according to the motion of the appliance unit 130. The inside skin 120 includes a lower inside skin 120a forming the jaws and an upper inside skin 120b forming a facial part other than the jaws.
In this android face robot, means for making facial expressions includes a mouth structure for implementing the motion of the mouth. The mouth structure of the android face robot is designed to be almost similar to the mouth structure of a human being in order to give a feeling of intimacy with a human being. Furthermore, the mouth structure of the android face robot is designed to move an upper lib (i.e., another element to make facial expressions).
The conventional android face robot, however, does not have a tongue that is one of several elements for making facial expressions or has only an imitation tongue having a simple form. Accordingly, the conventional android face robot is problematic in that it finds difficult to make more various facial expressions.
There are devices that simulate the motion of a tongue, but most of the devices have problems in that the devices are difficult in maintenance and repair and require a high production cost because they have complicated structures and that the devices cannot be applied to the android face robot owing to its large size.